Alright, sorry for that, it seems that when I implemented the key bindings code the checks for restricted mode were suddenly being bypassed. This should now be fixed in trunk and in the 2.2 branch with r4520. I'm putting up a test tarball at http://www.nano-editor.org/dist/test/nano-2.2.6pre1.tar.gz if you'd like to give it a try and let me know if it works for you.